It's amazing to me how often I see the suggestion to use Howard's products in speaker circles. You will never see them recommended in woodworking circles or proper furniture restoration forums. Howard's products, especially Feed -n- Wax are not wood finishes. The are soft waxes with various solvents and distillates that provide no protection to the wood surface. Restore-a-finish is loaded with solvents that will actually eat the existing finish. BE VERY CAREFUL WITH IT! This isn't typically a problem with an oiled Klipsch speaker since the original oil finish is within the wood. It penetrates and oxidizes in the wood to protect it (which is why it's the best type of finish for this applications and you want to duplicate it). Howard's products are the darlings of the antique world because they are simple to use, provide immediate visual results (so would rubbing with olive oil) and are used on finishes that are typically well worn and dirty. You can slather it on without cleaning and especially in the case of Feed n Wax- it has the fresh lemony scent and it's shiny! It does nothing to protect the wood and in fact like Pledge or anything else you find in the super market, it will have to be removed before a proper finish can be applied.
You are much better off simply cleaning the surface with mineral spirits and 0000 steel wool than using Restore a finish. The cardinal rule in approaching an existing finish is 'do no harm'. Restore a finish is like starting with a nuclear bomb. With an oil finish you simply want to clean off the surface so that the next oil finish you apply can penetrate the wood grain, oxidize and protect the wood. Using Feed -n- Wax is like rubbing mayonaise on the speaker. It will make it shiny. It will blend scratches. What it wont do is cure into a dry protective finish. In fact it will sit on the surface, remain wet and tacky and collect dust and fingerprints like crazy. So after you clean them, use an oil finish like they do at the Klipsch factory when your speakers were born. I recommend the 'natural' (colorless) danish oil if you are not trying to blend in existing finish damage. An oil finish will naturally darken over time, no need to add additional color. Apply it according to manufactures directions. Flood the surface and keep applying until it stops absorbing over the course of an hour or so. Then wipe it dry with a clean cotton rag. Let it cure at least 24 hours- longer if it's cooler weather or high humidity. Give plenty of time between coats- at least 24 hours. The finish has to oxidize. If you apply an additional coat too early it will start to get gummy and you will have to start over with the mineral spirits and 0000 steel wool. 2 or 3 coats should be plenty. With the last coat wipe with the grain and leave it undisturbed for a couple of days to really harden. Properly applied this finish will only need to be touched up every few years. Each coat will increase the durability of the finish.
I'm not here to argue about this. This information is no different than you would hear in any respectable wood working or furniture restoration forum where Howard's products are an ongoing joke. An oil finish is easy if you follow the steps and more importantly beautiful and durable.